Jesus, as the Amen, told the Church of the Lukewarm that the ones He loves, He reproves and disciplines (Revelation 3:19). In Hebrews 12 we learn not only about laying aside sin that slows down our run (verse 1), but also about God’s discipline.
He disciplines us for our good, that we may share his holiness. For the moment all discipline seems painful rather than pleasant, but later it yields the peaceful fruit of righteousness to those who have been trained by it. (Hebrews 12:10-11)
As sons, when we are subject to the “Father of spirits” we live (Hebrews 12:9).
In Romans 6 we’ll be reminded that Christians are sons and slaves. God is our Father and our Master. He is righteous, He frees us to be righteous, He instructs and strengthens and disciplines us that we might see the fruit of righteousness.
There are two kinds of pain: the pain of discipline or the pain of destruction. According to the word of the Lord, the pain of discipline leads to peace. The pain of destruction leads to more pain.
My son, do not despise the LORD’S discipline
or be weary of his reproof,
for the LORD reproves him whom he loves,
as a father the son in whom he delights.
(Proverbs 3:11–12 ESV, quoted in Hebrews 12:5-6)
Be wise, receive His corrections that bring about the blessings of obedience.